Reversible fan



Feb; 3, 1931 A. SCHUCHARDT REVERSIBLE FAN Filed Oct. '7. 1923 'INVENTOR BY l M.

ATTORNEY.

, customary to reverse the direction of rotation Patented Feb. 3, 1931 eneus'r sonnormnnr, or sea. Louis, ivrrssonnr REVERSIBLE FAN I Application filed October 7, 1929. Serial No. 397,935.

This'invention relates to certain new and useful improvements in reversible fans, the peculiarities of which will be hereinafter fully described and claimed.

The main objects'of my invention are to provide a fan casing adapted to be changed in its spiral wall to correspond to the direction of rotation of the fan-proper; secondly, to make such adjustment without changing the fan casing fastening to the foundation or base; thirdly, to preserve the effectiveness of operation of the fan which ever direction it may be rotated; and fourthly, to make such corresponding change of the fan casing quickly,and while the fan is running.

In the accompanying drawings on which like reference numerals indicate correspond ing parts, i

Fig. 1 represents a side elevation of a fan casing exemplifying my invention;

7 Fig. 2, a horizontal sectional plan view on the line 22 of, Fig. 1; 1

Fig. 3, a partial section on the line 33 of Fig. 1;

Fig. 4:, a similar view on the line 4+ of Fig. 1;

Fig. 5, a detail view showing the j ointpiece and adjacent portions of the spirals; and

Fig. 6, a similar detail of bottom portion of the casing and the adjacent portions of the spirals. 7

"Referring tothe drawing, thenumeral 5 designates a horizontal shaft on which is mounted a suitable fan proper 6. This shaft may be that of an attrition mill in which it is to secure a more effective operation when the grlndlng parts are worn by continuous rotation in one direction. In the usual construction it is'necessary to remove the fan casing I ,In my present construction, this reversal of the spiral is quickly efiected without'moving the casing. My casing comprises a pear shaped side wall 7 bolted or otherwise secured to an opposite wall 8 to clamp or locate be tween them 111 grooves or slots a perlpheral interposed outer wall, the opposite portions 9 and 9a, "of which approach each other and form an outlet opening 10, preferably at the top as-shown in Fig. 1. This outer wall is permanently located between the said sides, and each half of it issuccessively used as the outer portion of an operating'spiral accord ing to the direction of rotation of the fan proper. v

When the fan rotates in the direction of the'arrow, Fig. 1, an inner wall portion 11 of the operative spiral extends from the bot tom of the outer wall up to a triangular joint [piece 12 at'the throat and is adjustable,pref-- erably by slidingly mounting it in a slot between adjacent flanges lg'andl on the side casing 8 and a center piece 15 respectively. This piece 15 is preferably symmetrical on a vertical plane X through the center of said shaft, and its periphery on both sides of the plane X corresponds to the inner portions of two opposite spiral walls, each of which cooperates with and continues the spiral wall portions 9 and 9a of said outer wall by successive adjustments. A spiral wall in either direction towards the outlet can thus be formed as desired, and either one of them can be adjusted to operative position and the other one to inoperative position.

This center piece is preferably supported in its position in the side 8 by fastening'plates 23 and 24 at the top and bottom respectively, and'by a cross bar 16 or other means, encircling an inlet pipe 22 for said center piece 15. The said piece 15 is offset from the side 8 and held by extended bolts 25 to allow space for adjustment of slidable pieces 11 and 11a. Other fastening 'means may be employed. This sliding adjustment of the inner spiral portion 11 makes it a continuation of the outer spiral portion 9 and forms an operative spiral from the outlet 10 to said joint piece 12. An adjustable closing piece 17 curved or otherwise, extends from said joint piece or throat to the side of the outlet opposite the end of the outer spiral portion 9, and closes the space at the right between the adjacent outer spiral wall portion 9a and the inner spiral wall portion 1.1. A heart-shaped insert piece 18 is preferably fastened at its top by bolts 19 to side casing 8 and has flanges.

20 and 20a spaced from matching flanges 21 and 21a on the side casing 8, to form slots to receive said closing piece 17 and an opposite piece 17a respectively. These pieces also function as guide vanes for the exiting air.

The operative spiral wall required for rotation in the direction of the arrow Fig. 1, therefore, consists of the outer wall portion 9, the inner spiral wall portion 11 slid inward (Fig. 2) and the closing piece 17 slid inward. \Vhen the fan is reversed these movable pieces 11 and 17 are slidingly adjusted outward in the slotted casing side, and a reverse spiral wall is formed by the outer spiral portion 9a, an opposite inner spiral wall portion 11a slid inward, and an opposite closing piece 17a slid inward in their respective slots.

These slidable pieces are preferably withdrawn so that their inner edges are flush with the inside of side casing 8 and still fill the spaces between the flanges to prevent air leakage as illustrated by 11a at the left in Fig. 2.

Thus when the shaft of the fan proper is reversed in rotation, it is only necessary to adjust the slidable pieces as above described to change the spiral wall portions according to the reverse direction of the fans rotation.

I claim:

1. A fan casing comprising two flat pearshaped sides, an interposed peripheral wall located between said sides and curved to constitute the outer portions of two opposite spirals, and adjustable curved slidable pieces mounted in one of said sides and adapted to be positioned to constitute respectively the inner portion of and co-operate with one of the opposite spirals, substantially as described.

2. A fan casing comprising two sides, an interposed peripheral curved wall portion forming an outlet, adjustable slidable inner wall pieces oppositely curved and adapted to co-operate with respective portions of said outer wall and form a spiral in either direction,one of said sides having correspondingly curved slots for mounting said slidable pieces, substantially as described.

3. A fan casing comprising two sides with curved periphery, interposed permanent outer wall portions forming an outlet, adjustable inner wall portions adapted to co-operate with the outer wall portions and form an the inoperative portion of the outer wall,

substantially as described.

a. A fan casing coinprlslng two side walls, interposed outer walls forming an outlet, ad-

justably sliding plates forming inner spiral walls and co-operating with said outer walls,-one side wall havlng a heartshaped piece spaced therefrom forming slots extending from the inner walls to each side of the outlet, and adjustably sliding plates mounted in said slots forming guide vanes for the exiting air substantially as described.

5. A fan casing comprising side walls and interposed outer walls forming an outlet, adjustable inner walls adapted alternately to co-operate with the outer walls and form opposite spirals, a triangular joint piece connecting the side walls at the inner end of said spirals, and adjustable closing walls each of which is adapted to form a guide vane for one of said spirals when adjusted and connecting said joint piece with an outer wall at said outlet, substantially as described.

6. A fan casing comprising two sides, an interposed peripheral wall located between to said sides, and curved to constitute the outer portions of two opposite spiral passages, and adjustable spiral walls adapted to slide into and out of cooperating position, to form, alternately, the inner portions of said opposite spiral passages, substantially as described.

7. A. fan casing comprising two side walls and interposed peripheral outer walls and inner opposite spiral walls adapted to be positioned between said side walls,-one side wall having a center portion spaced from the outer portions thereof and fastened therein forming slots corresponding to the inner spiral walls and having guiding flanges, a joint piece connecting said sides at the top of said center portion, and adjustable closing plates adapted to be positioned alternately above the joint piece and so to cooperate respectively with the inner walls, substantially as described.

8. A fan casing comprising two side walls,

interposed peripheral curved outer walls located between said sides and forming an outlet, adjustable opposite spiral inner walls adapted alternately to be positioned so as to lead to said outlet and to cooperate respectively with said outer walls to form alternately opposite spiral passages, and closing plates adjustably mounted near the outlet adapted to be positioned alternately and connect a respective inner wall with the outer wall at said outlet, substantially as described.

9. A fan casing comprising two side walls, interposed peripheral curved walls and inner opposite spiral walls adapted to be po- Hill sitioned between said side walls,-one side wall having a center portion spaced from 1 outer portions thereof and forming opposite spiral slots therewith and having an inlet, a pipe connected to said inlet, and a crossbar spaced laterally away from said side wall and supporting said pipe,the spiral inner walls being adapted to be positioned in said slots and slidable between said crossbar and side Wall, substantially as described.

In testimony whereof I have aflixed my signature.

' AUGUST SOHUCHARDT. 

